Cut the chicken breasts in small pieces and season them with the garlic cloves (sliced) and a pinch of salt for grilling mix.Cut the bell pepper in half and take the white part out. Brush it with olive oil.Stuff it with the pieces of chicken breast and the mushrooms. Top it with the mozzarella.Bake in the oven to 210ºC for about forty minutes.Season with a pinch of thyme just before serving.Enjoy!